Re: [PATCH] PR69699 document why __GLIBCXX__ macro is useless

2017-01-19 Thread Jonathan Wakely
On 17/01/17 15:36 +, Jonathan Wakely wrote: The closest thing we have to a version macro in libstdc++ is __GLIBCXX__ which holds the valid of gcc/DATESTAMP from the source tree. That's useless for version checking or feature testing because snapshots have arbitrary values and there's no total

[PATCH] PR69699 document why __GLIBCXX__ macro is useless

2017-01-17 Thread Jonathan Wakely
The closest thing we have to a version macro in libstdc++ is __GLIBCXX__ which holds the valid of gcc/DATESTAMP from the source tree. That's useless for version checking or feature testing because snapshots have arbitrary values and there's no total order across branches (a later date does not mea